Yesterday, a man said he saw _______ UFO in the park. The police are looking for _______ UFO now.
It rained heavily this morning, but _______ of my classmates were away from school.
— Can you lend me your bike?— Yes. But you can only ________ it for one day. Because I’ll ride it to school the day after tomorrow.
— _______ will you stay in Shenzhen for your summer vacation?— For about two weeks.
— Must I return the book tomorrow?— No, you ________. You can keep it for three days.
Three fourths of the ________ in the country have run out.