If you say, “I had to study a lot this week”, it indicates that the act of studying was started and completed. However, by saying, “I have had a lot of studying this week”, it indicates that while you had a lot of studying so far this week, there might be more studying to come. Get more information on how to learn American English online with us here: ▶ https://gonaturalenglish.com/prereg Join Go Natural English on social media! → Facebook: https://facebook.com/gonaturalenglish → Twitter: https://twitter.com/gonaturaleng → Instagram: https://instagram.com/gonaturalenglish → Youtube: https://goo.gl/ogjdBV About Go Natural English: In regular English classes, you learn English grammar and English vocabulary, and in our English speaking lessons, you'll learn English the Go Natural English way - with advice to help you speak English like a native, with real English conversation and listening practice. Here you'll finally learn American English with a focus on English speaking skills. Unlock the English speaking world and finally understand English conversation. Learn how to speak English fluently with our English speaking course! Get more information on how to learn American English online with us here: https://gonaturalenglish.com/prereg