deepen

"The efforts were intensified"; "Her rudeness intensified his dislike for her"; "Pot smokers claim it heightens their awareness"; "This event only deepened my convictions";

"The debate intensified"; "His dislike for raw fish only deepened in Japan";

"They deepened the lake so that bigger pleasure boats could use it";

"His voice began to change when he was 12 years old"; "Her voice deepened when she whispered the password";