Lexical ambiguity or syntactically ambiguous?

B has no subject to the imperative verb.

Craven is correct, tryagain. The understood subject is always "you" in that type structure; however, I would say "Put the box on the table that is in the kitchen." That would clarify the modifiers a wee bit.

Thank you for the points you make.

Can I then assume b) is syntactically ambiguous as (the syntax, or grammar, can be understood in more than one way)

"The box already on the table, and to be put in the kitchen? Alternatively, is the box to be put on the table, which is in the kitchen?"

However, in sentence a) is ?'bank' not equally ambiguous as it could mean blood, sand, river etc.