Thank native English speakers very much again in advance.

1a. No explanation would be given other than given by him.
1b. No explanation would be given by other than him.
Question:
Which is grammatically correct?
Do both have the same meaning?

2a. Music left no room in his life for hobbies other than bowls and nature study.
2b. Tom , in his life, has more than three hobbies , his main hobbies (being) music, bowls, and nature study, and music being his best hobby.

Which is grammatically correct?
Do both have the same meaning?

Question

Thank native English speakers very much again in advance.

1a.  No explanation would be given other than given by him.
1b.  No explanation would be given by other than him.
Question: 
Which is grammatically correct?
Do both have the same meaning?

2a. Music left no room in his life for hobbies other than bowls and nature study.
2b.   Tom , in his life,  has more than three hobbies , his main hobbies (being) music, bowls, and nature study, and music being his best hobby.

Which is grammatically correct?
Do both have the same meaning?

Answer

1. both are acceptable (different ways to express the same meaning.) 
 
2a. Music left no room in his life for hobbies other than bowls and nature study.

2b.   Tom , in his life,  has more than one hobby , his main hobbies (being) music, bowls, and nature study, while music being his top hobby.

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