eaches us not to regret over yesterday, for it ________ and is beyond our control.

I don’t really work here,I untilthe new assistant arrives.

disease will produce a powder poison that will kill the patient.

I _________ her not to walk on the thin ice but she wouldn’t listen.[ ]

When you meet a new word in reading the English papers, you can guess its meaning but needn’t always ______ the dictionary.