1、Although not a diplomat, he can proficiently use diplomatic terms.
他虽然不是外交官，却能熟练地使用外交辞令。
2、It's difficult to keep several languages proficiently under your belt.
同时使用几种语言是很困难的。
3、I've just learned to curb my fears and adapt to change a bit more proficiently than I used to.
不同的是，我已经学会了控制恐惧以及加以利用它。