Can you clear up my doubts about these sentences?

My bike’s battery is discharged is definitely passive. The battery is acted upon not acting.
Active would be : I discharged my bike’s battery.

A good rule of thumb is that active means the subject of the sentence is the doer of the action. Active voice sentences always have subject-verb-object, although the object might not be specific or might be understood.
“My bike’s battery is discharged.” is a passive sentence.
“My bikes battery has discharged.” is an active sentence (object understood to be itself.)

Is the battery discharged, or is it flat?

Still sure it’s a passive and not a past participle adjective?

The use if the present form “is” indicates that if it were the passive voice, it’s a regular occurrence. Manipulating the sentence into the active voice would actually result in “I discharge my bike’s battery”.

It’s important to consider agent and patient when discussing passives, and whether or not you’re referring to a state of a noun or an action performed on the noun when deciding whether a s + be + past participle construction is either a passive verb phrase or a noun + complement phrase.

I agree with @the100thmonkey

Not all participles can be modified by “very”, but if the participle can be modified by “very”, then it’s a clear sign that it’s a participle adjective and not a passive.

My bike’s battery is very (much) discharged.
So it’s not passive.

“It was not very expected from you” – I think this sounds ok to me as well, so it’s also not passive. But your mileage my vary.

@lessonenglish in the second sentence, “it” is the subject whether the verb is passive or not.

Good heavens! I would love to give you an answer, but embarassingly, I don’t even understand the question! Sorry :o(

Aside from what everyone else has said, note that every sentence doesn’t have to be active. Sometimes a passive sentence sounds better, and once in a while it just makes more sense.

I am wondering if I am out of my depth on this site as, whilst I am no genius I am not stupid either. HOwever it is plainly clear from this question and the responses I am woefully lacking. Iam new to this site and have been enjoying it tremendously so far. I have only made a response as this was a question that had been selected for me as something that may be suitable for me, so I thought it would be rude not to give a response of some sort even if it was of no help at all. Sorry.
Rainbowspirit :o(

@rainbowspirit: Just chill, dude. You don’t always have to have a response for every question thrown at you. To be honest, I often have trouble answering the questions thrown at me as well, but if I feel I can provide a solid response to the question or at least add a new perspective then I’ll participate in the conversation. Otherwise, I just ignore the question and stop following it. Just participate in the conversations you’re comfortable with.

@Link – Damn straight.

You’ll find me not answering most questions, but usually being very grumpy on the ones I can answer!

Hahaha.