Did you write those sentences yourself before reading them out loud for the MP3 recording ??  If you did, bravo !

The American [r] sounds a lot more like the Mandarin [ㄦ] / [er] than the British [r] which sounds exactly the same as when you say the word "uh"

Go to
    https://www.oddcast.com/home/demos/tts/tts_example.php?sitepal
and hear the difference for yourself

I myself have been trying to imitate the British [r] sound    I recommend you do the same
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British [r] vs American [r].jpg

，

You should be careful about how you make the  [ l ]  sound when the letter  " l "  is at the end of a word like  " call "

There should NOT be any  " r " sound, in other words, definitely  " l r "


[ l ]  are NOT the same as [ r ]

Go to
    https://www.oddcast.com/home/demos/tts/tts_example.php?sitepal

Select  VOICE = "Jennifer {US)"

Try  " seal "  vs  "sear"

Q1:
  可以再提供几个练口语的网站吗？

A1:
  Let me know if you have any problem seeing or downloading from here

    https://www.kekenet.com/Article/kkspeech/usaspeech/

  REF:  https://muchong.com/bbs/viewthread.php?tid=10504598&authorid=2488597

Q2:  先把基本音节捋一遍，然后再练单词和句子发音，行吗？

A2:

  不行 !!

  Everyone can say "Hello"  like a native speaker

  But can you say a whole sentence, or a whole paragraph like a native speaker ?

  Native speakers have been hearing and saying whole sentences for 4+ years WITHOUT seeing words on a chalkboard in kindergarten

  Adult foreign learners don't have nor need 4 years*, but they do need to imitate a native speaker's voice, and do so diligently



* Yes, I am saying "from the ground up" is NOT RIGHT for learning to speak English

  "Bottom-up"  might be right for learning to write English... if you can get into the habit of always re-writing WHOLE sentences 3 different ways