________ you are leaving tomorrow， we can eat dinner together to

________ you are leaving tomorrow， we can eat dinner together tonight.
A、For
B、Since
C、Before
D、While
【正确答案】：B
【题目解析】：since在这是既然的意思，用在此处合适，而while当连接词时的意思有：1当....的时候；2然而；3虽然、尽管；4只要，用在此处意思都不合适。