We'llhaveapicnicneartherivertomorrow

問題詳情：

We'll have a picnic near the river tomorrow ________ it rains heavily. (眉山)

A．until    B．if      C．unless   D．when

【回答】

C　點撥：unless在意義上相當於。選C。

知識點：連詞

題型：選擇題