IN A SENTENCE:

The YOKE that cows or buffalo carry on their neck to plow the fields is heavy and hard which is entirely opposite to the yellow YOLK of the egg that is light and soft.

DISCLAIMER: I am not an English Native Speaker nor an expert in English language. What I write here are all from experience and research. If you feel I am out of line or say the wrong things, please alert me in the comments. To this effect, I am not immuned to these confusing words myself and this series is as much as an education for me as to those who read these blog posts.

PHOTO SOURCE: LINKEDIN.COM

YOKE and YOLK

YOKE

... can both be a VERB and a NOUN. As a VERB, it refers to USING the device, that is the YOKE, to pull something, for example. As a NOUN, it refers to the device that is carried by animals usually on their necks to pull something, like a plow.

PHOTO SOURCE: THEIDOLBABBLER.COM

Example #1: (NOUN) Animals carry the YOKE to easily pull things like a wooden cart.
Example #2: (VERB) It is stronger and better if we YOKE two cows together when plowing the barren field.

YOLK

... is a NOUN which refers to the yellow and circular element found inside an egg of a chicken or duck. Sometimes it can be reddish or orange(ish).

PHOTO SOURCE: THESMARTCANINE

Example #1: The YOLK of the egg is said to have high cholesterol content and should be avoided whenever possible.
Example #2: A sweet delicacy called Leche Flan contains mainly of egg YOLKS and condensed milk.

FURTHER STUDY:
http://writingexplained.org/yoke-vs-yolk-difference
http://grammarist.com/usage/yoke-yolk/
https://www.thoughtco.com/yoke-and-yolk-1689534
http://www.homophone.com/h/yoke-yolk
http://www.grammarbook.com/homonyms/yoke-yolk.asp

I hope we learned something new today. I surely did! See you in the next confusing words! If you like this series, please follow @cjclaro and upvote and resteem ;-)