Re: It is better to do your homework and complete it carelessly than not to complete
The end of #2 is grammatical but overly wordy. It can be shortened in several ways.
Originally Posted by Jit833
The key to my house is not working well because it is a duplicate key.
My house key is not working well because it is a duplicate key.
My front door key isn't working well because it's a duplicate.
In BrE, the key to the main door of your house is usually referred to as the "front door key".
Remember - correct capitalisation, punctuation and spacing make posts much easier to read.