Opinion by
Van der Voort, J.,This appeal arises by appellant’s challenge to his judgment of sentence. At trial on April 17, 1974, the judge, sitting without a jury, sustained appellant’s demurrer to a charge of possessing an instrument of crime, found appellant guilty on an indictment charging conspiracy, and found appellant guilty of criminal trespass on an indictment charging burglary and attempted theft by unlawful taking.1 Sentencing followed. Appellant now challenges the conviction of criminal trespass, arguing that the crime of criminal trespass is not a lesser included oifense of the crime of burglary. If criminal trespass is a lesser included offense of burglary then appellant was properly adjudged guilty of the lesser offense. Commonwealth v. Nace, 222 Pa. Superior Ct. 329, 295 A.2d 87 (1972).
The statutes in question are those regarding "Burglary” :
*379“(a) Offense defined. — A person is guilty of burglary if he enters a building or occupied structure ... with intent to commit a crime therein, unless the premises are at the time open to the public or the actor is licensed or privileged to enter.” [Emphasis supplied] Crimes Code,2 Section 3502 (a),
and “Criminal Trespass”:
“(a) Buildings and occupied structures.— (1) A person commits an offense if, knowing that he is not licensed or privileged to do so, he enters or gains entrance by subterfuge or surreptitiously remains in any building or occupied structure ....” [Emphasis supplied] Crimes Code, Section 3503 (a) (1).
The language of the “Crimes Code” regarding burglary comes from the “Model Penal Code”, Section 221.1. The fundamentals of the crime, entering a building with criminal intent, are similar to burglary under our former “Penal Code”.3 We turn to the case law under our former statute to determine the elements of the crime. “The elements of burglary are the intent to commit a felony and the successful and effective overt act directed toward the commission of the felony by the wilful and malicious entry into a building. Commonwealth v. Procopio, 200 Pa. Superior Ct. 226, 188 A.2d 773 (1963)....” Commonwealth v. DelMarmol, 206 Pa. Superior Ct. 512, 516, 214 A.2d 264, 266 (1965). Constructive, although incomplete, entry, as by a portion of the body only, satisfies the entry requirement of the crime. Commonwealth v. Myers, 223 Pa. Superior Ct. 75, 297 A.2d 151 (1972). Commonwealth v. Garrett, 423 Pa. 8, 222 A.2d 902 (1966), notes that the common law crime of burglary has been expanded in its concept, but that wilful and malicious entry are still *380needed. For present purposes, we note that under the current statute, which is bolstered by case law under the former statute, the operative concepts for the crime of burglary are entry, intent to commit a crime within the building entered, and lack of a license or privilege to enter.
The crime of criminal trespass, also modelled upon the “Model Penal Code”, is new as a statutory crime in Pennsylvania. It did have its precursors in laws to prevent wilful trespass upon lands of state institutions,4 wilful trespass upon private lands which had been posted,5 entry “in a manner not amounting to burglary” with intent to commit a crime therein,6 entry by force,7 forcible detain-er,8 and certain others. In examining these, we see that the element of the crime is unlicensed or unprivileged entry. Intent to commit a crime during the time inside the structure is n|i>t common to all of this category. See, for example, Commonwealth ex rel. Madden v. Ashe, 162 Pa. Superior Ct. 39, 56 A.2d 335 (1948).
It is clear that to be a lesser included offense all its essential elements must be included in the greater offense. Commonwealth ex rel. Moszczynski v. Ashe, 343 Pa. 102, 21 A.2d 920 (1941); Commonwealth v. Nace, supra. The greater offense includes the lesser. Commonwealth v. Bailey and Ford, 92 Pa. Superior Ct. 581 (1927).
Finding that essential elements of the crime of criminal trespass are unlicensed or unprivileged entry into a building or occupied structure and that these elements are included in the crime of burglary, we hold that the *381crime of criminal trespass is a lesser included offense of the crime of burglary. Therefore, on an indictment for burglary, there may properly be a verdict or finding of guilty of the lesser included offense of criminal trespass upon proof beyond a reasonable doubt of unlicensed or unprivileged entry into a building or occupied structure.
Appellant claims that the statute on criminal trespass should be interpreted to require proof that his entry was “by subterfuge”. The language upon which he centers his claim appears from the Act to be as follows:
“ (1) A person commits an offense if, knowing that he is not licensed or privileged to do so, he enters or gains entrance by subterfuge or surreptitiously remains in any building or occupied structure.”
The appellant claims that to prove an entry which is not licensed or privileged the Commonwealth must show an entry by subterfuge. He claims that the words, “by subterfuge” modify the words, “he enters”. The Statutory Construction Act of 1972 provides that “words and phrases shall be construed according to the rules of grammar and according to their common and approved usage.”9 It appears clear that the words in the statute “if, knowing that he is not licensed or privileged to do so he enters ... any building...” may properly constitute a criminal trespass. Entry alone is an element of the crime and is not limited by any additional requirement of “subterfuge.”
Appellant argues that the Commonwealth failed to prove that he was not licensed or privileged to enter the premises in question. Contrary to his contention, the Commonwealth met its burden of establishing the unprivileged nature of entry by introducing into evidence appellant’s statement, which is against his penal interest, to-wit, that he walked into the house because he knew that there was *382piping therein which he could remove and resell. There is no doubt that proof of unlicensed or unprivileged entry is the Commonwealth’s burden. The burden of proving necessary elements of a crime cannot be shifted onto the defendant. See Commonwealth v. Stoffan, 228 Pa. Superior Ct. 127, 323 A.2d 318 (1974). Testimony by one Charles Ellis indicates that he was the record owner on the date of the offense and that he had given appellant no permission to enter. Further testimony shows that the house may have been unoccupied and “boarded up”. There is no indication that the house had been abandoned in the sense of that word’s definition: “Abandoned property is that to which the owner has voluntarily relinquished all right, title, claim and possession with the intention of terminating his ownership, but without vesting it in any other person, and with no intention of reclaiming possession or resuming ownership and enjoyment in the future. 1 Am J 2d Aband §1.” Ballantine’s Law Dictionary, Third Edition, “abandonment of property”.
Judgment of sentence affirmed.
Watkins, P.J., concurs in the result.
. Appellant was acquitted of the charges of bürglary and attempted theft.
. Act of 1972, Dec. 6, P.L. 1482, No. 334 (18 Pa. C.S. §3502 et seq.)
. Act of 1939, June 24, P.L. 872, Section 901 (18 P.S. §4901).
. Act of 1971, Aug. 6, P.L. 275, No. 69 (18 P.S. §4955).
. Act of 1967, Sept. 1, P.L. 303 (18 P.S. §4954). This is now encompassed in Section 3503 (b) of the “Crimes Code,” supra, dealing with defiant trespassers.
. Act of 1939, June 24, P.L. 872 (18 P.S. §4901.1).
. Act of 1939, June 24, P.L. 872 (18 P.S. §4403).
. Act of 1939, June 24, P.L. 872 (18 P.S. §4404).
. Act of 1970, November 25, P.L. 707, No. 230, 1 Pa. C.S. §1903 (a).