Omitting Parts of Verbs

When compound verbs in the same sentence share a common element, that element does not need to be repeated.

• We have received your letter and forwarded it to our Liverpool office. (The helping verb have is shared by the two main verbs, received and forwarded.)
• We can and will achieve these goals. (The main verb achieve is shared by the two helping verbs, can and will.)

However, do not omit any element when different parts of the main verb are required.

• wrong: I never have and I never will forget what you have done for me.
• right: I never have forgotten and I never will forget…

• wrong: We have and still are asking for an accounting of the assets.
• right: We have asked and are still asking for…

Source: The Gregg Reference Manual