Hi
For changing the read more text in slider go to Appearance >> Editor >> Header.php here you can find the text read more and change it with your language.
For read more text in blog go to Appearance >> Editor >> content-single.php here you can find the text and change the text with your language.
For contact form go to Appearance >> Editor >> custom-functions.php and find contactform text there you can see all the static text you can change it with your language.
Thank You