I want a pen pal from Canada.这句话对吗?还有是write a letter to sb还是write letter to sb?I want a pen pal from Canada.这句话对吗?并说明理由还有是write a letter to sb还是write letter to sb?↑只能选一个或者两个一块选

应该是 I want a pen pal who is from Canada. who 是引导后面的从句 ，指代pen pal
write a letter to sb： 写信给某人
其中 a letter 可以省略 即 write to sb
write a letter to sb=write sb a letter

不对，应该是I want a pen pal who is from canada,write a letter to sb

I want a pen pal from Canada这句话是对的.
因为信是可数的,所以要加a,write a letter to sb:给某人写信.

I want a pen pal from Canada.这句话是对的
write a letter to sb