Question

4. Henry can’t attend the party        (hold) at Tom’s house at present because he is preparing the speech at the party       (hold) at Marie’s house tomorrow.

Answer 1

4. being held;to be held 現(xiàn)在分詞的被動語態(tài)作后置定語表示動作正在進行，相當(dāng)于定語從句which is being held;不定式的被動語態(tài)表示將要發(fā)生的動作。