present
|
past
|
future
|
conditional
|
|
---|---|---|---|---|
s1 |
occur
|
occurred
|
will occur
|
would occur
|
s2 |
occur
|
occurred
|
will occur
|
would occur
|
s3 |
occurs
|
occurred
|
will occur
|
would occur
|
p1 |
occur
|
occurred
|
will occur
|
would occur
|
p2 |
occur
|
occurred
|
will occur
|
would occur
|
p3 |
occur
|
occurred
|
will occur
|
would occur
|
present
|
past
|
future
|
conditional
|
|
---|---|---|---|---|
s1 |
am occurring
|
was occurring
|
will be occurring
|
would be occurring
|
s2 |
are occurring
|
were occurring
|
will be occurring
|
would be occurring
|
s3 |
is occurring
|
was occurring
|
will be occurring
|
would be occurring
|
p1 |
are occurring
|
were occurring
|
will be occurring
|
would be occurring
|
p2 |
are occurring
|
were occurring
|
will be occurring
|
would be occurring
|
p3 |
are occurring
|
were occurring
|
will be occurring
|
would be occurring
|
present
|
past
|
future
|
conditional
|
|
---|---|---|---|---|
s1 |
have occurred
|
had occurred
|
will have occurred
|
would have occurred
|
s2 |
have occurred
|
had occurred
|
will have occurred
|
would have occurred
|
s3 |
has occurred
|
had occurred
|
will have occurred
|
would have occurred
|
p1 |
have occurred
|
had occurred
|
will have occurred
|
would have occurred
|
p2 |
have occurred
|
had occurred
|
will have occurred
|
would have occurred
|
p3 |
have occurred
|
had occurred
|
will have occurred
|
would have occurred
|
affirmative
|
negative
|
|
---|---|---|
s1 |
-
|
-
|
s2 |
occur
|
don't occur
|
s3 |
occur
|
don't occur
|
p1 |
occur
|
don't occur
|
p2 |
occur
|
don't occur
|
p3 |
occur
|
don't occur
|