
Regular verb: contribute - contributed - contributed
Present | Present continuous | Preterite | Preterite continuous | 
| I contribute you contribute he contributes we contribute you contribute they contribute  | I am contributing you are contributing he is contributing we are contributing you are contributing they are contributing  | I contributed you contributed he contributed we contributed you contributed they contributed  | I was contributing you were contributing he was contributing we were contributing you were contributing they were contributing  | 
Present perfect | Present perfect continuous | Pluperfect | Pluperfect continuous | 
| I have contributed you have contributed he has contributed we have contributed you have contributed they have contributed  | I have been contributing you have been contributing he has been contributing we have been contributing you have been contributing they have been contributing  | I had contributed you had contributed he had contributed we had contributed you had contributed they had contributed  | I had been contributing you had been contributing he had been contributing we had been contributing you had been contributing they had been contributing  | 
Future | Future continuous | Future perfect | Future perfect continuous | 
| I will contribute you will contribute he will contribute we will contribute you will contribute they will contribute  | I will be contributing you will be contributing he will be contributing we will be contributing you will be contributing they will be contributing  | I will have contributed you will have contributed he will have contributed we will have contributed you will have contributed they will have contributed  | I will have been contributing you will have been contributing he will have been contributing we will have been contributing you will have been contributing they will have been contributing  | 
Present | Present continuous | Past | Past continuous | 
| I would contribute you would contribute he would contribute we would contribute you would contribute they would contribute  | I would be contributing you would be contributing he would be contributing we would be contributing you would be contributing they would be contributing  | I would have contributed you would have contributed he would have contributed we would have contributed you would have contributed they would have contributed  | I would have been contributing you would have been contributing he would have been contributing we would have been contributing you would have been contributing they would have been contributing  | 
Infinitive | Imperative | 
Infinitive | Imperative | ||
| to contribute | contribute Let's contribute contribute  | 
Present | Past | ||
| contributing | contributed |