English .....Are these two sentences correct?

Grammatically nothing wrong with those sentences. But constructionwise, that word "furthermore" doesn't fit. It is more the kind of word you would use in a letter of complaint LOL. Substitute "In addition, during my career etc. etc." More straightforward, less "pompous". In the second sentence, assuming that you are providing references from those employers, I think it would be better to let their own words, in those references, speak for themselves. But you could put in your letter of application something like this:.....

"I take pride in my work, and have always directed my efforts towards both achieving, and going beyond employer expectations". When this is matched to what those previous employers themselves have to say about you in their references, their words, and your own, will be seen to coincide very nicely, and, I am sure, impressively.

Your sentences are not that bad, but they need tweaking. You need to provide us with context in order to determine the truest fit. I don't know if your first sentence is related to the preceding sentence or two, in order to use "Furthermore". It doesn't seem to work. Too wordy. Some suggestions:

"As an electrical technician at __Ltd., I helped (or supported) system maintenance."

or,

"During my career as an electrical technician at __Ltd., I was the assistant to system maintenance."

or,

"During my career as an electrical technician at __Ltd., I assisted system maintenance."

Your second sentence sounds all right, but you need to clarify the expectations. Give a few examples. . . . delivers job completion before deadlines . . . delivers early job completion . . . delivers accurate analyses, etc.

And, expectations are an average mark. You don't want to sound average. You want them to think you go beyond expectations. Good Luck!

"Furthermore, during my career as an electrical technician in ..........Ltd., , I assisted in THE maintenance of the system."

"My employers often refer to me as an employee who delivers all expectations ASKED OF HIM PROMPTLY AND EFFECTIVELY"

That is what I would add, I hope this helps.

The grammar is correct in both. However - I think the wording could be better. 1. I have seen a cat that jumps on and off the roof of my car leaving its footprints. 2. I saw a cat that jumped on and off the roof of my car leaving its footprints.

For the second sentence I'd suggest "fulfills all expectations"

"as an experienced electrical technician in ..., I maintained and supported XYZ systems"

"meets all expectations"

I would suggest, "...I assisted in maintaining the sytem."

(Verbs paint a more "active" picture.)

And for the second, I would say "...meets or exceeds all expectations."

Good luck

You have excellent grammar! I'm impressed! Yes, your statements are fine.

only one comma after LTD

sound's good enough to me?good work carry on.