I wasn't sure how fast to go.

我不确定有多远。

I'm not sure about rhyming perestroika with balalaika.

我不知道perestroika是否与balalaika押韵。

I'm not sure about the practicality of their plan.

我还无法确定他们的那个计划的可行性如何。

He stood awkwardly in the doorway, not sure what to say.

他尴尬地站在门口，不知道该说什么。

He’s a kind of unofficial adviser,but I’m not sure exactly what he does.

他像是个非官方顾问,但说不好他究竟是干什么的。

I am not sure if these props will stay in long enough to do the work.

这些支柱能否维持到工作结束, 我对此没有把握。

I understand some of the concepts of the theory but I'm not sure about its details.

"我懂得这个理论的一些概念,但对详细内容可不大清楚。"

I am not sure what value it adds to determining public, or for that matter private, policy.

我不能肯定它对确定公众政策或就此问题而言，对确定个人决策能增添什么价值。

I’m not sure about Johnson—we’d better keep tabs on him until we know we can trust him.

我对约翰逊不太放心——我们最好先观察他一段时间，直到我们确信可以信任他。

I let some lemonade fall on my clothes, and I'm not sure if I can wash it off.

我把柠檬汁洒在衣服上了, 不知道能否把它洗掉。

I guess the children's sign on the right means it's a children's gite but I am not sure.

旁边的小朋友标志是不是儿童客栈的标志我还没有查到。

I'm not sure whether he is trying to be clever or controversial, but either way, such writing smacks of racism.

我不知道他是想显示自己聪明还是想引起争论，但不管怎样，这样的文章打击了种族主义。

I’m not sure if Jerry will be at work today—he was out on the piss with his mates last night.

我不知道杰里今天能不能上班，他昨晚跟朋友去酒馆喝了很多酒。

You were strangled to death with a plastic sack. It's probably an odd thing to hear - I wasn't sure how to sugarcoat it.

你确实被个塑料袋套上给闷死了。可能听着挺怪的，我不晓得怎么说才能好听点。

The doctors are making the right noises about the reforms to the health service, but I’m not sure that they actually agree with them.

提到医疗改革医生都随声附和，可我不敢确定他们是不是真心赞同。