Yes, but they'd have to be trying to get fat.
If you're an ectomorph who's trying to become fat, here are some tips.
1. Eat more meals per day. This makes you less full.
2. Eat lots of junk food. Cake is excellent.
3. A high fat, high sugar diet promotes intestinal bacteria that aren't metabolically efficient and store fat. This way, your metabolism dies down.
There are three major body types - ectomorphs, endomorphs and mesomorphs. Ectomorphs - have minimal muscle and minimal fat. An example would be a marathon runner. Endomorphs - have lots of fat. They have a pear shaped body. An example would be a sumo wrestler. Mesomorphs - have lots of muscle and have a 'V' shaped body. A prime example would be a gymnast.
By their slim or linear body types
Slim or Linear body types.
Slim or linear body types
by doing the opposite of How do you become fat?
The same way as everyone else.
You don't. You become fat by eating lots of calories.
Then you will become fat yourself
You can become fat because of a medical condition. You can become fat if your food intake exceeds your energy output.