Here is a book where you can find some tips and exercises to improve you writing skill before doing the TOEFL IBT. [Remember that you have to practice some months in advance in order to master these kind of skills.]
In the Reading Section of the Test, you'll find some reading texts like the one above and eight questions per text to measure your reading comprehension. The lines are numbered for you to find them rapidl
In the Toefl test you will a Grammar section that is divided into two parts. One of them is this one, the Structure Section. You'll find fifteen exercises like this:
The TOEFL iBT test measures your ability to use and understand English at the university level. And it evaluates how well you combine your listening, reading, speaking and writing skills to perform academic tasks.
There are two formats for the TOEFL test. The format you take depends on the location of your test center. Most test takers take the TOEFL iBT test. Test centers that do not have Internet access offer the Paper-based Test (PBT).