____you stepped into the lab with yourshoes on You are supposed to take them off before you enter it.

If we don’t study hard, we will ______in our class.

（2014届江西省重点中学盟校高三第二次联考英语试卷）30. －Lydia, what did our head-teacher say just now?－Every boy and every girl as well as the teachers who _____ to lead the group _____ asked to be at the school gate before 6:30 in the morning.

In 1492, Columbus ________ on one of the Bahama Islands, but he mistook it for an island off India.[ ]

Alice is one of the students who I am sure always best in most difficult situations.