1.account
I have an account with the bank. 我在银行开有户头。
He turned/put his knowledge of Spanish to good account. 他善加利用他对西班牙语文的知识。
Don‘t stay away on account of John. 为了约翰,不要离开。
2.act
Don‘t take him seriously —— it’s just an act. 不要把他看得太认真 ——— 他只是假装那样而已。