10 Kill two birds with one stone 一石二鸟

To complete two tasks together, with less effort than doing them separately
Example: Since I’d gone to the store to buy some bread, I thought of killing two birds with one stone and invited Mr. Biggs to the party.

11 Be in a black mood 情绪极差

To be so negative about everything that it is impossible for anyone to reason with him/her
Example: My father has been in a black mood for days, we dare not say anything to him.

12 New blood 新成员

New people brought into an organization to introduce different and original ideas
Example: It was decided to bring new blood into the school by employing teachers with the latest training.

13 Feeling blue 感到无精打采

Feeling sad or depressed
Example: She’s feeling blue, because the man she loves is far away.

14 Get to the bottom of something 弄清真相

To find out the truth about something
Example: I’m trying to get to the bottom of why David left without saying goodbye.

15 A piece of cake 轻松的事

Something which is very easy to do
Example: Here…let me put the batteries in for you. It’s a piece of cake.

16 Pay a call 拜访

To visit somebody
Example: As we’re in this neighborhood, we might as well pay the Jacksons a call, we haven’t seen them for ages.

17 By chance 偶然, 意外的

Unexpectedly; with no prior planning
Example: By chance, I bumped into my wife in the shopping mall
18 Round the clock 夜以继日的

To do something continuously, without a break or pause
Example: The ambulance services worked round the clock hauling people trapped in the building to safety.
19 Keep one’s cool 保持冷静

To stay calm in a difficult situation
Example: If the traffic is jamed, the only thing to do is keep your cool, or get out of the car and walk!
20 In a tight corner 处于困境

In an extremely difficult situation
Example: Whenever I get into a tight corner, I try to rely on quick thinking to get out of it.