For example, we often drop the d after an n  before a consonant . So, look at this word:  

Friendly. We don't make that D sound,  it comes after an n before a consonant. 

This happens a lot in plural nouns  and third person conjugations like  

"ends". "The show ends at midnight." 

"Lands" "My flight lands at eleven." 

Also, apostrophe s. "Band's" 

"The band's going to go on  soon." No d, no d, no d. 

It also happens when two words  go together like "Found my". 

"Look everybody, I found my phone!" No d. "Stand for" "What does it stand for?" No d.