When correcting grammar in a ms Word document what does “passive voice” mean?

Question

English is not my first language and I use Microsoft Word as a tool to correct my English when I'm writing. I'm not sure what's meant by "passive voice" and how I'm supposed to correct it.

Examples:

"The boys had all left to be with their fathers and I was chosen to look after the goats."

"was chosen" is marked as passive voice.

And,

"The sprouts could be eaten as they were and the roots had to be roasted on coals."

Where "could be eaten" is marked as passive voice.

Could you explain what I'm doing wrong so that I can avoid it in the future?

Answer 1

Here is a site which explains active and passive voice very clearly, and gives lots of examples.

http://owl.english.purdue.edu/handouts/g...

It has sentences which are changed to be written first in the active voice, then in the passive voice, showing you how to change your sentences from passive to active voice.  

Most English instructors prefer that their students not use passive voice in their writing.  I don't know why; I was an English teacher, and I seldom found a problem, unless there was some other error also involved in the sentences written in passive voice.

Answer 2

Passive voice is a verb tense that doesn't indicate who is doing the action.  Who chose you to look after the goats?  Who could eat the sprouts?  Here are some examples of active voice using the sentences you gave:

"The boys had all left to be with their fathers and their mothers chose me to look after the goats."

"We could eat the sprouts as they were, but the roots had to be roasted on coals."  

Answer 3

The passive voice is when the action expressed by the verb is performed upon the subject of the sentence, as opposed to the active voice when the subject performs the action.  There is nothing wrong with using the passive voice, although using it excessively can result in an awkward style.

To change the first sentence to active voice:

The boys had all left to be with their fathers and [whoever] chose me to look after the goats.

Unless the context suggests otherwise, I would leave the second sentence in the passive voice.  However, I would recommend changing "and" to "but."