Every time when something ____ me, I turn on the radio and listen to music.

Where’s your father?—He __________ to Singapore for a meeting. He ________ there twice.

Be sure _______ when you enter the cave. Otherwise, you’ll hit your head on the rocks.

It ______ that he has been ill for a long time.

Every individual _________ in a continually changing world of experience of which he or she is the center.