Here is your text with the adjustments. I've erased all the redundant information, which made it easier to read. Next, I added some suggested places in which you should insert your sources.
I haven't put the text's correction here because it exceeded the character limits.
I hope you can continue adjusting your text and make it even better!
Answer:
I believe the linking word is Sounded
Explanation:
C and B. A past tense refers to the past. Crawls is currently doing, was crawling could be either present or past, so if you have a multiple choice that would be one of them. C is crawled, meaning he was. And D is will crawl, meaning the future.
True they also have done electrical gadgets,nanotechnology
