I can just scrape by on what my parents give me.

我靠父母给的那点钱只能勉强度日。

You might just scrape by with a C.

你可能只能勉强得到一个 C 。

So he would scrape by as well.

所以他倒是可以勉强通过。

He works 50 hours a week and still only earns enough to scrape by.

他每周工作50小时，仍然只能勉强维持生活。

Borrowing money from friends and relatives helped him to scrape by.

通过和朋友及亲戚借债，他勉强度日。