Do we fall back on的用法和樣例：
例句
- Doctors sometimes fall back on old cures.
有時醫生們求助於老的療法。 - We had to ask the government for help.
我們不得不求助於政府。 - The men fell back to previously prepared positions.
士兵們退到事先準備好的陣地。 - We were reduced to rely on naked diplomacy.
我們已退到了只能依靠純外交辦事的地步。 - We will discuss the problem later.
這個問題我們回頭再說。
