Tom is taller than _____ in his class.
The skirt _________is made of silk is very expensive. I can’t afford it.
—Can you guess if they ________tomorrow? —They will come if they ________free, I think.
My grandparents _________for fifty years and they are both quite healthy now.
—Where is Jack? —I noticed that he ________the teacher’s office just now.
—Don’t worry. Your uncle is coming to help you. —________he doesn’t come?