MODAL VERBS - best selection of exercises I've seen so far

http://www.grammar-quizzes.com/modalsum.html

Another reason I won't run for this office ;)

Being a president is bad for your health

http://www.bbc.com/news/health-35102077

Learn English online - more MOOCs

A massive open online course (MOOC) is an online course 
aimed at unlimited participation and open access via the web 

https://www.edx.org/course/conversational-english-skills-tsinghuax-30640014x-0

https://www.edx.org/course/english-grammar-style-uqx-write101x-0

https://www.edx.org/course/english-composition-asux-eng101x-credit-eligible

https://www.coursera.org/learn/ingles-empresarial-gestion-liderazgo

Can air make you fat? Wait till you hear the last studies on pollution and obesity

http://www.bbc.com/future/story/20151207-the-air-that-makes-you-fat

Can you have your dream job and make money?

http://www.bbc.com/capital/story/20151211-its-your-dream-job-but-the-pay-is-a-nightmare

Remember when they go in a sentence?

Time to revise WOULD

Got kicked out? What's next?

http://www.bbc.com/capital/story/20151207-this-is-why-how-you-handle-rejection-says-a-lot-about-you

Are you your own enemy?

http://www.bbc.com/capital/story/20151208-actually-youre-the-problem

From chaos to order - grammar exercises on Sentence Structure

https://www.ego4u.com/en/cram-up/grammar/word-order

http://www.englisch-hilfen.de/en/exercises_list/satz.htm