主要区别:
start to do的意思是，即将要准备开始去做某事，事情还没有做还在准备阶段，一般现在时；
start doing的意思是开始做某事，事情已经开始做了，不包括准备阶段，是现在进行时。
具体区别:
1) 表示开始一项长期活动或开始一种习惯时，使用doing.
（此时start/begin doing多用于表示开始一项较长时间或经常性的活动）
How old were you when you first started playing the piano?
你几岁时开始弹钢琴？
2) begin, start用进行时时，后面动词用不定式to do
I was beginning to get angry。
我开始生起气来。
3) 在attempt, intend, begin, start 后接know, understand, realize这类表示心理状态或精神活动的动词时，常用不定式to do。
I begin to understand the truth。
我开始明白真相。
Mary started to guess what is in the bag. 玛丽开始猜包里有什么东西了。
4) 物作主语时
（句子主语是物不是人的时候,后用start to do sth）
It /The snow began to melt.雪开始融化。
扩展资料
start to do造句
From start to finish he believed in me, often more than I did myself.
他自始至终都相信我，而且时常超过我对自己的信任。
I'll start to think about it when I have to write my report.
我要写报告时会对此予以考虑的。
The machines start to wear down, they don't make as many nuts andbolts as they used to.
机器开始出现磨损，螺母和螺钉的产量不如从前了。
As the plants grow and start to bear fruit they will need a lot of water.
当植物生长并开始结果的时候，它们需要大量的水。
The cells will promptly start to soak up moisture.
细胞会立即开始吸收水分。
start doing 造句
I really ought to start doing something. I'm starting to get a potbelly.
真的应该做运动了，我都开始长啤酒肚了。
After you've stated that enough is enough, you then need to start doingsomething about it.
当你说的足够多了，那就需要为此做些什么了。
You can't get very far until you start doing something for somebody else.
当你为别人做了些事情，你才能走得更远。
So start doing something with your oil.
所以，用你们的石油，开始做点什么事情吧。
No matter what your passion is, get out there and start doing something.
不论你的激情是什么，马上行动起来，开始做些事情。
参考资料: 百度百科-英语语法