The word "meanwhile" is a conjunctive adverb that joins two clauses together. It’s similar to "as" and "while." It’s useful in describing two things happening at the same time.
examples
1. He’s cleaning the house; meanwhile, his wife is away at work.
2. Kimlan is studying engineering; meanwhile, her friend Hoang is in the United States studying English.
Kimlan
Hoang
3. Sue is vacationing in Hawaii; meanwhile, her coworkers in Chicago are hard at work inside their offices.
4. The beekeeper checks his hives to see how his bees are doing; meanwhile, the bees continue to do their work.
5. A high school band marches in a parade; meanwhile, the truck behind them entertains the crowd with a flame thrower.
6. Hanging clothes outside to dry saves me money on electricity; meanwhile, the environmental benefits of not using electricity for such a simple task should be obvious.
7. The tomatoes in the front yard are almost ripe; meanwhile, the tomatoes in the backyard aren’t even close to being ripe.