1) I can understand French perfectly.
法语我完全懂.
2) That's all Greek to me.
我完全不懂。
3) I don't fully understand.
我不完全懂。
4) I don't understand French.
我不懂法语。
5) I could not make top or tail of it.
我完全弄不懂。
6) It's (all) Greek to me.
这我完全不懂。
参考词条