Oh，by the way (順便說一句)

By the way, could you do me a favor?

順便說一下，你能幫我個忙嗎?

Before I forget(趁我還沒忘)

Before I forget, do you have plans for tomorrow night?

哦，趁我沒忘，問下你明天晚上有安排了嗎?

That reminds me(…讓我想起)

That reminds me of my first dog.

哦，那讓我想起我養(yǎng)的第一只狗……blahblahblah

Speaking of(說到/提起…)

Speaking of pets，I really miss my first dog

嗯，說到寵物，我實(shí)在很想念我養(yǎng)的第一只狗……

While we are on the subject…(既然談到這個話題)

While we are on the subject of money, may I ask when you will repay the loan?

既然說到錢的話題，我能知道你什么時候會還這筆貸款呢?