Speaking Practice 1

 
A: 您好！ (You said 你好 instead of 您好.)
B: 您好！ (It was better the second time.)
A: 请问，您贵姓？( It sounded like "對" rather than "貴.")
B: 我姓李， 叫李马力。请问，您姓什么？( It sounded not clear enough, but being a little bit like "美." )
A: 我姓宋，叫宋华。您是哪国人？

(The pronunciation of 宋 was perfect; the one of "國" sounded like the third tone rather than the correct one, the second tone. )
B: 我是美国人，是北京大学的学生。 (As for 生, you mispronouced the first tone as the fourth tone.)
A: 认识您很高兴。
B: 认识您，我也很高兴。 (You mispronouced the third tone as the fourth tone.)

A: 您好！ 

B: 您好！
A: 请问， 您贵姓？

問 although this is spelt "wen", it's pronounced "wun", it kinda rhythms with "dun" and "lun. In the north of China, this "w" changes into something closer to an English "v". My main teacher is a proper Beijinger, and thus I have been taught to speak like this (I happen to like it, too)
B: 我姓李， 叫李马力。请问，您姓什么？

李马 - two third tones in a row change 2 + 3. Therefore it should be lí mǎ. Also, it sounds like you said li mai or li bai, I can't quite tell. Careful. 
A: 我姓宋，叫宋华。您是哪国人？

宋 - this should be much more nasal both times you say it. Listen out for this when you listen

是 - this is just a bit wrong, don't really know how to explain this one

國人 - two second tones in a row. The first one was good, but you actually changed the second one into a 4th tone. Exphasise the second one more, and perhaps making a deliberate effort to start the second one at a lower pitch (because you've just gone up in pitch on the first one, right?) and go up more (because second tones are hard) will help you do this. 

華 just make sure this ends in an "a" sounds, it's ever so slightly off.
B: 我是美国人，是北京大学的学生。

是 - is still a bit off

國人 is off. 國 was alright, but 人  sounded like a fourth tone again.

學生 you said xue1sheng4, it's xue2sheng1, be careful. 

A: 认识您很高兴。
B: 认识您，我也很高兴。

You say wo3ye4hen3. It should be wo2ye2hen3. 

Here is me. I sound like a foreigner, but it might help you get the idea. (Best to get a native to do it, don't sit and listen to me haha). 

Medium speed:http://vocaroo.com/i/s1AXBdQ6KIvk

Slow: http://vocaroo.com/i/s0agNDs7MLvv

Laurence

It is really pretty good, I can understand what you said, but you should pay attention to these characters below.

贵 gui    fourth tone

马 ma.  third tone

国. guo.  second tone

keep up your good work

Correction of only the English:

Speaking Practice 1

Hi,
I decided that I have to focus much more on more pronounciation (especially the tones) when learning Mandarin. Vocab and characters alone won't cut it.. Especially because pronounciation is always my main problems when learning languages.
Therefore I decided to record myself while reading the following text. Bear in mind that I am really at the very beginning of my Mandarin learning and therefore am purposely speaking slowly to focus on getting the tones right. Speed will come much later; first I have to manage to even get it right while speaking that slowly.

Audio:

http://vocaroo.com/i/s0IhKSQk4ksB

Listening to that I realize that I really have to invest MUCH more time in pronounciation.

Here is the text:

A: 您好！
B: 您好！
A: 请问， 您贵姓？
B: 我姓李， 叫李马力。请问，您姓什么？
A: 我姓宋，叫宋华。您是哪国人？
B: 我是美国人，是北京大学的学生。
A: 认识您很高兴。
B: 认识您，我也很高兴。