If you want to truly sound like a CHINESE Chinese, there’s no getting around it, sooner or later you are going to have to learn to grunt. The truth is, rather than using 是, 对 or the verb of the question, one of the most common ways to respond to a statement or question is to simply say (though I think ‘say’ is pushing it) 嗯 ng or 啊 a (the latter with varying intonations, depending upon the circumstance). To Anglos, this can feel a little too ‘primitive’ or ‘impolite’, but really, it’s no different in status or acceptability to any other sound that comes out of our vocal tract, so you should feel free to embrace the colour of language and give these interjective replies a go. Just one word of advice, many dictionaries give the Pinyin for 嗯 as en, but if you really pronounce it that way, you will sound like a bit of a fool. It should really be ng, almost approaching mm. Anyway, here’s a few examples showing how you can use these.
A: 你知道“菠萝”是什么意思吗？ ‘Do you know what ‘boluo’ means?’
B: 是pineapple的意思吧。 ‘It means ‘pineapple’, right?’
A: 啊。 Yes.
A: 我穿这个很难看。 ‘I look ugly in this.’
B: 嗯。 That’s right.
A: …
A: 我买了一台新的电脑了。 ‘I’ve bought a new computer.’
B: 真的吗？ ‘Really?’
A: 嗯。 Yep.
中文秘诀 | The Secret of Chinese 