二．现在进行时：is / am / are + 现在分词

1．表示现在正在进行的动作。如

►. The kettle is boiling. Shall I make tea?

►. Don't you think you eat too much? You're putting on weight（体重增加）。

►. The workers are building a new bridge across the river.

2．表现阶段正进行的动作。

►. He is taking physics this semester（本学期）。

►. Weare preparing for our final examination this week.

3．go, come, leave, arrive, land, meet, die, start, return, join, etc. 用于进行时态时表示即将开始的动作。

►. Look! The bus is coming.看！车来了！

►. The old man is seriously ill, and he is dying.

►. Alice is leaving for Beijing with her mother.

4．与 always, forever, continually, constantly 等副词连用，表示说话人带有感情色彩：赞赏或厌恶。

►. He is always thinking of others.（他总是想着别人。）joozone.com