Chemical pollution will bring about a threat to agriculture and food chain, and ________ to human health.
The plant is dead. I ________ it more water.
I promised to get there before 5 o’clock, but now the rain is pouring down. They ________ for me impatiently.
It was playing computer games that cost the boy plenty of time that he ________ have spent doing his lessons.
—________ I return the dictionary within three days? —No, you ________. You ________ keep it for five days.
Sir, you ________ be sitting in this waiting room. It is for women and children only.