@蓝大卫,

This is a very good question. A lot of people get confused there. Yes, you got it right. I said 2nd 3rd 3rd. If you see three third tones together, you just need to see the meaning of this three characters. For instance, in the phrase 给我买, the meanings of 给 and 我 are closer. In this case, you should change the tone of 给 to the second. Some people change both of the tones of 给 and 我 to the second. It's correct too. If the meanings of the second and third character are closer, for example, 老祖母 (old grandmother), you should say it as lao3zu2mu3.

--Echo

Echo,

In the sentence, 别给我买鞋 bié gěi wǒ mǎi xié

I know that if there are two third tone words in succession that the first third tone is spoken as a second tone. What is done if there are three in succession. Did I hear you correct speak this

as 2nd 3rd 3rd?

In other words, only one third tone changes to a second?