243.

W: David, we shouldn't sit here doing nothing.

M: Why not? It's Saturday afternoon, isn't it?

W: Yes, but there's so much to do around the house.

M: It can wait.

W: We ought to finish washing down the kitchen walls and cupboards.

M: We can do that tomorrow. We don't have to do it today.

W: All right. That's a good idea.

M: Talking about washing down the kitchen-where's Bob?

W: He's having lunch with Georgia.

M: What! Again?

W: He should be back soon.

M: He shouldn't spend so much time with that girl.

W: You must be patient, David. Nineteen's a very difficult age, you know?

M: Yes, I know. But he ought to be studying more.

答案解析：

(1) 正確答案為B。根據It's Saturday afternoon, isn't it?現在是周六下午，不是嗎？可知，對話發生的時間為下午，因此B項正確。

(2) 正確答案為C。根據女子說We ought to finish washing down the kitchen walls and cupboards.我們要清洗廚房的墻壁和壁櫥。和男子說We can do that tomorrow. We don't have to do it today.我們可以明天再做。我們不必非得今天做。可知，二人打算明天清楚廚房，因此C項。

(3) 正確答案為A。根據He's having lunch with Georgia.他在和喬治婭吃午餐?？芍U勃現在在餐廳，因此A項正確。