不明確だ
This sentence is unclear.
この文は不明確です
This sentence is quite unclear.
この文はかなり不明確です
This sentence is quite unclear right to the last part.
この文は最後の部分までかなり不明確です
The relation between subject and object in this sentence is quite unclear right to the last part.
この文は主語と目的語の関係が最後の部分までかなり不明確です
The relation between subject and object in this sentence is quite a bit less clear than in the others, right to the last part.
この文はほかの文より主語と目的語の関係が最後の部分までかなり不明確です